Improvement in adjustable rocking-chairs



N. P'. BRADISH. Adjustable Rocking-Chair.

No. 212,123. Patented Feb. 11,1879.

NJETERS, PHOTO-UTHOGRAPH Fj, WASHINGTON, D c,

Unrran S'rArEs PA'rENT Gretna.

NELSON P. BRADISH, OF JERSEYVILLE, ILLINOIS.

IMPROVEMENT IN ADJUSTABLE ROCKING-CHAIRS.

Specification forming part of Letters Patent No. 212,123, dated February 11, 1879;

application filed October 11, 1878.

To all whom it may co nccra:

Be it known that 1, NELSON P. BRADIsH, of Jerseyville, in the county of Jersey and State of Illinois, have invented anew and Improved Adjustable Chair; and I do hereby declare that the following is a full and exact description of the same, reference being had to the accompanying drawings, and to the letters of reference marked thereon.

The invention herein described relates to an improvement in adjustable chairs of that class in which the back and seat are adapted to be set at any required inclination to each other, and difl'ers from other chairs of its class mainly in the locking mechanism by which the back and seat are secured in the required position relative to each other.

The object of the invention is to provide an adjustable chair in which the locking mechanism shall be out of sight, strong, simple, and easily actuated, yet possessing all the most desirable features of more complicated and expensive devices for the same purpose.

In the accompanying drawings, in which similar letters of reference indicate like parts, Figure 1 is a sectional side elevation of the chair, taken through the center, exhibiting the locking mechanism under the seat. Fig. 2 is an enlarged plan view of the seat turned upside down. Fig. 3 is a still larger sectional side elevation of the locking mechanism, detached from the chair.

In Fig. 1, A represents the seat of the chair, supported upon a frame, E, the sides of which project rearward, and are connected with the rockers'F by pivots 0, about which the seat is adapted to vibrate. B represents the back of the chair, supported upon the rockers by side bars, I), which include between them the seatframe, and extend downward to the forward part of the rockers, to which they are pivoted atf, the point upon which the back oscillates.

Between the bars I) I), Fig. 2, is pivoted, at 1 r, a cross-bar, O, in which is inserted a rod, 1), which passes through the eye of, and engages with, a clasp, S, inserted in a cross-bar, D, pivoted between the sides of the seat-frame E, as shown at t t. The manner in which the clasp S acts upon the rod 1) will be readily understood by reference to Fig. 3, in which the clasp is shown in section, and is somewhat exaggerated in thickness, in order to exhibit clearly its action upon the rod 1).

It will be observed that when the back of chair is brought forward as far as possible, in about the position shown in the drawings, Fig. 1, its inclination is still backward, and conse* quently it tends to draw the rod 1) through the eye of the clasp S.

It will be noticed that the clasp is inserted in the bar 1) at a point sufficiently remote from, and in advance of, the axis of suspension of said bar to cause the diagonally-opposite edges of the eye ofsaid clasp to impinge automatically upon the rod 19, and thus arrest its rearward motion; and, as the pressure against the back is increased, so the rod 19 tilts more and more the clasp S, the opposite edges of the eye of which are thus made to grasp with additional force the rod 1), and render its withdrawal by the tensile strain upon it impossible.

It will be still further observed that as the frame of the seat rests upon the cross-bar G, and as this cross-bar is pivoted to the frame of the back 13 at a point always behind an imaginary vertical line drawn through the pivots f, its effect, as also that of all superincumbent weight on the seat and pressure against the back, is to add to the rearward tension on the rod 2, and-consequently increase the gripe of the clasp S thereon.

In order to add to the weight of the rod 19, to keep the clasp S, under all circumstances, tilted for immediate action upon said rod, the seat-frame is adapted to rest on the front edge of the cross-bar O at the point a, Fig. 3, thus avoiding the employment of a spring or other similar device.

To unlock the chair, in order to lower the seat and increase the inclination of the back, it is only necessary to place the hand under the front edge of the cross-bar D and lift it. This movement brings the clasp S to a vertical position, and causes it to relinquish its grasp upon the rod 19, which will then slide ireely through the eye.

In raising the back and seat, it will, be observed that the rod 1) is thrust forward, which causes the eccentrically-pivoted clasp to relinquish automatically its hold upon said rod; consequently it is only when lowering the chair that the locking mechanism requires to be actuated by hand.

The result of these details is a very efiicient locking device, free from complicated parts, easily actuated, and not limited to fixed points of adjustment, as is the case where a series of equidistant notches or some similar device is employed.

What I claim as my invention, and desire to secure by Letters Patent, is-- In an adjustable chair, the locking device described, consisting of the rod 19, attached to the bars or legs I) b by the cross-bar O, in combination with the clasp S, attached to the bar D, pivoted to the seat or seat-frame E, substantially in the manner and for the purpose herein set forth.

This specification signed and witnessed this 6th day of October, 1878.

N. P. BRADISH.

Witnesses:

JAMEs A. LOOKE, A. G. HUGHES. 

